Help me understand cartridge alignment

I have said this before and will say it again. VTF, leveling, azimuth, and twist (horizontal alignment) are far more important than "optimum" spindle to stylus distance aka overhang. If you resort to a spherical stylus even twist is not crucial. An old hand at TT set-up once proved this to me. He wanted to hear my deck but did not want to spend the time to optimize set-up with a new cartridge. He said "you can slam the cartridge forward in the headshell, set VTF and azimuth and do an approximation of twist and the sound will be fine". The sound was amazing. So my point is that "alignment" is a nebulous term. Most of us define it as so-called perfect alignment including overhang or pivot to stylus which is only a compromise.

Everyone here is right.

But the most right are those with parallel trackers.  @lewm  This is the only condition in which there can be a linear relationship between cantilever/stylus correctly mounted in cantilever and groove.  Beware.  Many so-called high-end cartridges do not have accurately mounted stylii.  They are often out by a few degrees, nulling all the efforts we make in set-up.

Buy a TT from Upscale Audio and have them set It up. 😁

Clearthinker, Your remark about parallel tracking tonearms is totally beside the point, but someone will always bring up parallel tracking tonearms in a discussion about alignment, so you cannot be blamed. But it doesn’t help us or the OP to understand why he is happy with his SQ despite being 5mm off in alignment. My point is that tracking angle error (TAE), while it is best minimized, does not so obviously manifest itself as "distortion" in the electrical sense. For my evidence, I give you underhung tonearms with zero headshell offset angle. Such underhung tonearms can only achieve a single null point on the surface of the LP, where also the skating force is zero, and deliver gobs of TAE at the extremes of the arc across the LP surface, much more TAE than almost any "properly aligned" overhung tonearm with an offset headshell. And yet, my experience with two different examples suggests their TAE is relatively harmless to SQ.  I admit this is subjective evidence, and I have not made measurements.  But neither have the alignment police.

Beware.  Many so-called high-end cartridges do not have accurately mounted stylii.  They are often out by a few degrees, nulling all the efforts we make in set-up.

Uh,what does a linear tracker do to solve problems with stylii not mounted square to the cantilever?